1. Populations

2. Characteristics of Populations
Three important characteristics of a population are its geographic distribution, density, and growth rate.

3. Population growth factors
space (available range or territory), food, and predators
The number of births, the number of deaths, and the number of individuals that leave the population

4. Population Growth
Change in a population size is known as growth rate
If a population is provided with ideal conditions, it will continue to increase.

5. Exponential Growth
Occurs when individuals in a population reproduce at a constant rate.
This pattern of growth is in a J curve

6. Logistic Growth
As resources become less available, the growth of populations slows or stops!
This pattern of growth is an S shaped curve

7. S-Shaped Curve-Logistic Growth
Figure 5-4 Logistic Growth of Yeast Population
S-Shaped Curve-Logistic Growth
Section 5-1
Carrying capacity
Number of Yeast Cells
Time (hours)
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8. Carrying Capacity The point at which a population becomes stable.
It is the maximum, stable population size an environment can support over time.
A number of factors help stabilize the population at this size.
They are density-dependent and density-independent limiting factors.

9. Density-Dependent Limiting Factors
Competition
Predation
Parasitism
Crowding/Stress

10. Density-Independent Limiting Factors
Weather
Fires
Drought/Floods
Human Activities

11. Population density is the number of individuals that live in a defined area.
Population density is a measurement of the number of individuals living in a defined space.
Scientists can calculate population density.

12. Population dispersion refers to how a population is spread in an area.
Geographic dispersion of a population shows how individuals in a population are spaced.
Clumped
dispersion
Uniform
Random
Population dispersion refers to how a population is spread in an area.

13. There are three types of dispersion.
clumped

14. There are three types of dispersion.
uniform

15. There are three types of dispersion.
random

16. Concept Map Population Growth Logistic Exponential growth Limits on
Section 5-1
Population
Growth
can be
Exponential
growth
Logistic
characterized by
represented by
characterized by
represented by
Falling
growth rate
S-shaped
curve
Limits on
growth
No limits on
J-shaped
Constant
Unlimited
resources
which cause a
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